USEYRA Khan's parents were horrified when a sore throat triggered a rare disorder leaving their bubbly daughter unable to walk, talk or feed herself.

After five weeks of high temperatures and GP check-ups, the seven-year-old, of Girlington, Bradford, was finally diagnosed by hospital doctors with a little known condition that affects only a handful of children in the UK.

Blood tests, X-rays and scans at Bradford Royal Infirmary and Leeds General Infirmary revealed Useyra had Sydenham's Chorea which affects the brain and nervous system, explaining why she had become so fidgety - constantly moving her hands, head, lips.

Useyra's mother Rozina Yousaf said it was heartbreaking: "She was fidgeting all the time and couldn't stay still.

"We couldn't understand what she was trying to say to us, she couldn't stand or walk. She couldn't dress herself or feed herself anymore. She had to be carried everywhere. It was heartbreaking."

And she added: "Useyra was very unlucky to get this. It is so very rare. We had never heard about it before, neither had family, friends or her teachers - who have all been wonderful."

Eventually a heart scan at Leeds General Infirmary confirmed Useyra had caught rheumatic fever which had triggered the Sydenham's Chorea disorder.

The bacterial infection in her throat had fired up her immune system which then reacted against the parts in the base of her brain that control movement, causing her muscles to move rapidly and involuntary.

Bradford Teaching Hospitals NHS Foundation Trust paediatrician, Dr Sally Pollard said only a small proportion of people with streptococcal sore throats develop acute rheumatic fever, of which only some develop Sydenham’s Chorea which could last weeks or up to one year with the symptoms possibly coming and going for many years after that.

“There is no specific treatment for this condition but patients are advised to rest if symptoms are mild and to take sedatives if symptoms are severe, Dr Pollard said.

"Anti-epileptic medications can also be used and penicillin is recommended to prevent additional symptoms of rheumatic fever. Due to better sanitary conditions and the use of antibiotics to treat streptococcal infections, rheumatic fever and Sydenham’s Chorea are now rare in the developed world but more common in developing countries."

The heart scan also showed two of Useyra's heart valves were damaged because of the Rheumatic Fever and leaking, she is now on penicillin for life, said her mother to ward off any other infections.

She said: "Thanks to Allah she is improving with medication and is getting back control of moving her arms, legs and hands.

"We hope she will be able to go back to school at Whetley Academy for the first time since Christmas this week but just for an hour at a time.

"She still has to have lots of check-ups and more scans for her heart but we are just so grateful that we are getting our lovely, bright Useyra back."

Only a handful of cases of Sydenham's Chorea are found in the UK each year and it is most common in children aged between five and 15 with more girls than boys appearing to be affected.